Transcript Tower configurations - Vrije Universiteit Brussel

Tower configuration
Sensors and Actuators
1
3
5
2
7
6
7
5
5
4
1 Mechanical level sensor
2 Pressure level sensor
3 Visual level sensor
4 Controlled pump
5 Locations for :
5.1 Flow sensor
0/1
5.2 Controlled on/off valve
∆
5.3 Controlled variable valve
6 Location for outlet control valve
(for final competition)
7 Manual valves
(for configuration and test)
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Pump
Commercial aquarium pumps are used. It is possible to
adjust somewhat the pump power by using a simple
dimmer such as those used for lights.
As these pumps have important internal leakage, a one-way
valve has been inserted to avoid reversal of the waterflow
when the pump is stopped or runs at low power.
Two different
Pumps are proposed:
-Low power pump
-Medium power pump
Both use the same
control circuitry
Optical Fibers
OptoTRIAC
LED
220 V
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Overflow Prevention
To be installed in February 2008
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Mechanical Level Sensor
10KΩ
10 turns
0-5V
GND
+ 5V
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Pressure Level Sensor
P
-2 to 10 mV
Solid state
pressure
transducer
* 500
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0-5V
GND
+ 5V
Flow Meter
Hall effect
sensor
Instantaneous measurement mode
t
Q = 1/k.t
k = 752 pulses / liter
0/5V
GND
+ 5V
Integrating measurement mode
n pulses
Q = n/k.T
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T
Waterpeilmeting met Webcam
x cm
Webcam
(resolutie 640x480 pixels)
niveau (n cm)
PC
Water
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Waterpeilmeting met Webcam
480 pixels
y
pixelwaarde
Digitaal Beeld afkomstig van de webcam
Lucht/glas
water
0
480
p pixels
Absolute waarde
van de gradient
0
Detectievenster (manueel instelbaar)
y
480
y
p wordt bepaald door te zoeken
naar het maximum van de gradient
magnitude.
Detectie van de overgang tussen lucht en
water: discrete gradient magnitude van de
pixelwaarde in de y richting (binnen het
detectievenster).
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n=p*x/480
Control System Building Blocks
Bus
master
∆
∆
Bus
Slave
pc
Bus
Slave
pv
0/1
5V sensor
Bus
Slave
gp
EIA 485 instrumentation bus
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Pulse frequency
4-20mA DC control
Fiber optic link
24V DC control
Fiber optic link
0/1
0-5V signal
EIA serial link
USB
Bus
Slave
fm
Bus Master
• Interface between PC and EIA485 bus
• Personal Computer Interface :
– Serial EIA232 interface at 19200 b/s.
– Data format : 8 bits/char, no parity, one stop bit.
• EIA485 bidirectional bus :
–
–
–
–
–
Talk
: from master to slave, Red bus led on.
Listen
: from slave to master, Green bus led on.
Bus reset sequence : 0AH,0DH,0DH,0DH
Slave command : 0AH, 0DH, Command byte, Data byte.
Slave answer
: 0DH, Slave ID byte, Answer byte.
• Display :
– Left display
– Right display
: Command byte
: Data byte
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Bus Master FSM
State
Description
Bus
Transition Cause
Destination
0
idle
Tx
Sync_M
1
1
Master Initialization, step 1
Tx
Sync_S
# Sync_S
2
0
2
Master Initialization, step 2
Tx
Sync_S
# Sync_S
3
0
3
Master Initialization, step 3
Tx
Sync_S
# Sync_S
4
0
4
End of master Initialization
Tx
Sync_M
#(Sync_M and Sync_S)
5
0
5
Slave Synchronization
Tx
Sync_S
6
6
Slave Receiving Command
Tx
# Sync_S
Sync_S
7
3
7
Slave Receiving Data
Tx
Any byte
8
8
Slave transmitting
Rx
Spontaneous
9
9
Wait state
Rx
Sync_M
5
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Bus Slave
Common module
+12V
- 12V
RA0
RA1
RA2
RA3
RA4
RC2
+5V
gnd
PIC
Slave module V 2.1
+12V
- 12V
Bb
Ba
+5V
gnd
0 1
Id =
Lsb
Data
Command
msb
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Bus Slave
Common module
• Slave Commands : (0AH), 0DH, Command byte, Data Byte.
– Command byte :
• Four msb : Slave ID :
– 1 to 14 each ID unique on one bus.
– 15 = broadcast
• Four lsb : Command code:
– 0 = software reset
– 1 to 15 : device specific command.
– Most devices recognize only one command byte
– Data byte :
• Any value between 0 and 255
• Meaning is device specific
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Bus Slave
Common module
• Slave Answers : 0DH, Slave ID byte, Answer Byte.
– Slave ID byte :
• Four msb : 0000
– Reserved for future developments.
• Four lsb : Slave ID
– Number between 1 and 14.
– Answer byte :
• Any value between 0 and 255
• Meaning is device specific
• Broadcast messages are never answered
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Bus Slave
Common module
• Red LED Display
– Left Display: last Command byte accepted by slave
– Right Display : last Data byte accepted by slave
• Green Decimal Display
– Meaning is device specific
– Usually related to the answer byte send by the slave
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General Purpose Interface
• Inputs
– 0-5 V analog signal between RA0(+) and RA2(ref)
• Outputs
– On-off optical command on RA1
– On-off 24 V DC command on RA4
• Commands
– 0 : software reset
– 1 : copy data bits 1 and 4 onto RA ports 1 and 4 and measure
input
– 2 : measure analog input without affecting digital output
• Answer
– Rounded value of 8 most significant bits from AD converter.
• Decimal display
– Value of AD input in % of 5 V.
• Device ID’s
– First interface = 1; second interface = 9
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AD/DA Interface
(not yet available)
• Inputs
– 0-5 V analog signal with differential buffer
• Outputs
– 0-5 V buffered analog output, with 1s integrator.
• Commands
– 0 : software reset
– 1 : set analog output signal
• Answer
– Rounded value of 8 most significant bits from AD converter.
• Decimal display
– Value of AD output in % of 5 V.
• Device ID’s
– First interface = 4; second interface = C
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Pump Control
t
10 mS
t
10 mS
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t
10 mS
Pump Control
• Inputs
– Optical 50 Hz signal from pump power module
• Outputs
– Optical 100 Hz triac firing pulses with adjustable delay after
the 50 Hz reference input
• Commands
– 0 : software reset, switches off the pump.
– 3 : sets adjustable delay in the range 0-176 (=B0H) steps of
51μS. The smallest delay results in maximal pump power.
• Answer
– Echo of the command data byte.
• Decimal display
– Value of firing delay in multiples of 100 μS.
• Device ID’s
– First interface = 2, no additional interfaces useful.
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Proportional Valve Control
• Inputs
– none
• Outputs
– Valve control current, 4-20 mA. Valve is closed at 4 mA.
• Commands
– 0 : software reset, closes the valve.
– 2 : sets valve current in steps of 0.1mA, 0 = 0 mA, .
• Answer
– Current through valve before command was received,
expressed in multiples of 0.1mA.
• Decimal display
– Current in mA.
• Device ID’s
– First interface = 2; second interface = 10 (=AH)
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Flow Meter
(Version 1.0)
• Inputs
– Pulses from Dataflow compact flow transmitter
• Outputs
– none
• Commands
– 0 : software reset.
– 4 : request reading of the pulse counter
• Answer
– Time interval between successive pulse, in units of 0.4096 mS.
– 255 means underflow (out of time range)
• Decimal display
– Time interval, expressed in % of 100 mS
• Device ID’s
– First interface = 4; second interface = 12 (=CH)
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Flow Meter
(Version 2.0, not yet available)
• Inputs
– Pulses from Dataflow compact flow transmitter
• Outputs
– none
• Commands
– 0 : software reset.
– 4 : data byte = 0:enable pulse duration measurement
data byte = 1: enable pulse counting measurement
• Answer
– Mode 4.0 : pulse duration, in multiples of 0.4096 mS
– Mode 4.1 : Number of pulses in 105 mS.
– In both modes : FFH means “out of range”
• Decimal display
– In both modes : Fraction of full range in %
• Device ID’s
– First interface = 4; second interface = 12 (=CH)
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Prijslijst
Naam
Aantal
Beschikbaar
Small pump
175
3
3
Large pump
225
2
2
GP Slave Module
75 * funct
6
6
On-off valve
60
4
4
Mech.Level Sensor
10
4
4
Pressure Transd 100mb
75
4
?
Pressure Transd 10 mb
150
4
?
Var Pump Control
100
4
4
Var Valve with ctrl
500
3
2
Flow meter with ctrl
215
3
3
WebCam
250
2
1
AD/DA Slave Module + analog
400
4
1
Consultant communications
300 / hour
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Command Summary
Interface
ID1
ID2
CMND
General Purpose 1
9
1,2
Prop.Valve.Ctrl
2
A
2
Pump control
3
-
3
Flow Meter
4
C
4
DATA
D1= Pump on
D4= Valve open
D = 28H = 0 % open
D = C8H = 100 % open
D = 08H = max power
D > B0H = min power
D=0
(1) Commands with ID = 15 (=FFH) are broadcasts. Slaves don’t
generate answers to broadcast messages
(2) Command 0 followed by any data byte resets the interface
software and reads the ID switches. No answer is generated.
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